Cardiomyopathy is a serious disease of the heart muscle. Nearly 40 percent of children with cardiomyopathy receive a heart transplant or die within the first 2 years after diagnosis. The percentage of children with cardiomyopathy who received a heart transplant has not declined over the past 10 years and cardiomyopathy remains the leading cause of transplantation for children over one year of age. Studies from the National Heart, Lung, and Blood Institute (NHLBI)-funded Pediatric Cardiomyopathy Registry (PCMR) have shown that the cause of cardiomyopathy is established in very few children yet genetic causes are likely to be present in most. The incidence of pediatric cardiomyopathy is approximately 1 per 100,000 children. This is comparable to the incidence of such childhood cancers such as lymphoma, Wilms' tumor, and neuroblastoma. However, the published research and scientific conferences focused on pediatric cardiomyopathy is much less than for these other conditions. The purpose of the proposed conference, the Third International Conference on Cardiomyopathy in Children is to build on the success of the first conference, Idiopathic and Primary Cardiomyopathy in Children- Research Directions and Strategies held in 2007 (cosponsored by NHLBI and the Children's Cardiomyopathy Foundation), and the Second International Conference on Cardiomyopathy in Children held in 2010 (cosponsored by the Children's Cardiomyopathy Foundation and the Myocarditis Foundation with additional funding from the NHLBI-sponsored Pediatric Cardiomyopathy Registry) to review the current knowledge base from research on cardiomyopathy including research areas not covered in the first and second conferences. This meeting is designed to bring together a multidisciplinary group of scientists (entry-level, mid-career, and senior), including molecular biologists, epidemiologists and clinicians in order to disseminate the most up to date research on the prevention, etiology, diagnosis, mechanisms, and treatment of pediatric cardiomyopathy and to shape the direction of future research on the disease. It is anticipated that this interdisciplinar exchange of knowledge will identify data gaps and needs, future research directions and new approaches and technologies that will lead to a better understanding of this disease and improved intervention and prevention strategies.